Effectiveness of telephone-based screening and triage during COVID-19 outbreak in the promoted primary healthcare system: a case study in Ardabil province,Iran

Journal of Public Health - Screening services for early detection of patients is one of the important capabilities of the health system with a proper referral system. In the crisis of respiratory...     

Acoustic characterization of a miniature matrix transducer for pediatric 3D transesophageal echocardiography

This paper presents the design, fabrication and characterization of a miniature PZT-on-CMOS matrix transducer for real-time pediatric 3-dimensional (3D) transesophageal echocardiography (TEE). This 3D TEE probe consists of a 32?×?32 array of PZT elements integrated on top of an Application Specific Integrated Circuit (ASIC). We propose a partitioned transmit/receive array architecture wherein the 8?×?8 transmitter elements, located at the centre of the array, are directly wired out and the remaining receive elements are grouped into 96 sub-arrays of 3?×?3 elements. The echoes received by these sub-groups are locally processed by micro-beamformer circuits in the ASIC that allow pre-steering up to ±37°. The PZT-on-CMOS matrix transducer has been characterized acoustically and has a centre frequency of 5.8 MHz, -6 dB bandwidth of 67%, a transmit efficiency of 6 kPa/V at 30 mm, and a receive dynamic range of 85 dB with minimum and maximum detectable pressures of 5 Pa and 84 kPa respectively. The properties are very suitable for a miniature pediatric real-time 3D TEE probe.     

Erythropoietin attenuates motor impairments induced by bilateral renal ischemia/reperfusion in rats

Neurologic sequelae remain a common and destructive problem in patients with acute kidney injury. The objective of this study was to evaluate the possible neuroprotective effect of erythropoietin (EPO) on motor impairments following bilateral renal ischemia (BRI) in two time points after reperfusion: short term (24 h) and long term (1 week). Male Wistar rats underwent BRI or sham surgery. EPO or saline administration was performed 30 min before surgery (1000 U/kg, i.p.). Explorative behaviors and motor function of the rats were evaluated by open field, rotarod, and wire grip tests. Plasma concentrations of blood urea nitrogen (BUN) and creatinine (Cr) were significantly enhanced in BRI rats 24 h after reperfusion. BRI group had only an increased level of BUN but not Cr 1 week after reperfusion. Impairment of balance function by BRI was not reversed by EPO 24 h after reperfusion, but counteracted 7 days after renal ischemia. Muscle strength had no significant differences between the groups. BRI group had a decrease in locomotor activity, and EPO could not reverse this reduction in both time points of the experiment. Although EPO could not be offered as a potential neuroprotective agent in the treatment of motor dysfunctions induced by BRI, it could be effective against balance dysfunction 1 week after renal ischemia.     

Improved anticancer delivery of paclitaxel by albumin surface modification of PLGA nanoparticles

Background

Nanoparticles (NPs) play an important role in anticancer delivery systems. Surface modified NPs with hydrophilic polymers such as human serum albumin (HSA) have long half-life in the blood circulation system.

Methods

The method of modified nanoprecipitation was utilized for encapsulation of paclitaxel (PTX) in poly (lactic-co-glycolic acid) (PLGA). Para-maleimide benzoic hydrazide was conjugated to PLGA for the surface modifications of PLGA NPs, and then HSA was attached on the surface of prepared NPs by maleimide attachment to thiol groups (cysteines) of albumin. The application of HSA provides for the longer blood circulation of stealth NPs due to their escape from reticuloendothelial system (RES). Then the physicochemical properties of NPs like surface morphology, size, zeta potential, and in-vitro drug release were analyzed.

Results

The particle size of NPs ranged from 170 to 190 nm and increased about 20–30 nm after HSA conjugation. The zeta potential was about -6 mV and it decreased further after HSA conjugation. The HSA conjugation in prepared NPs was proved by Fourier transform infrared (FT-IR) spectroscopy, faster degradation of HSA in Differential scanning calorimetry (DSC) characterization, and other evidences such as the increasing in size and the decreasing in zeta potential. The PTX released in a biphasic mode for all colloidal suspensions. A sustained release profile for approximately 33 days was detected after a burst effect of the loaded drug. The in vitro cytotoxicity evaluation also indicated that the HSA NPs are more cytotoxic than plain NPs.

Conclusions

HSA decoration of PLGA NPs may be a suitable method for longer blood circulation of NPs.     

Cannabidiol promotes neurogenesis in the dentate gyrus during an abstinence period in rats following chronic exposure to methamphetamine

Metabolic Brain Disease - Chronic methamphetamine (meth) abuse can lead to certain deficits in the hippocampal function by affecting the hippocampal neurogenesis and plasticity. To determine...     

Fatty acid composition of ovule in kutum (Rutilus frisii kutum Komensky, 1901)

Fatty acid composition of ovules (ovulated oocytes) from kutum (Rutilus frisii kutum) was investigated to assess their relationship to gonad biological characteristics, larval size, fertilization, and hatching success. Forty-eight kutum were captured in the wild during the spawning season. Results revealed an inverse relationship between linoleic acid (18:2n-6) and ovule weight (P?<?0.05). Arachidonic acid (20:4n-6) and eicosapentaenoic acid (20:5n-3) contents showed a direct correlation with the number of ovules per gram (P?<?0.05); the latter had an inverse relationship with the ratio of surface to volume (P?<?0.01). There was a direct and significant correlation between docosahexaenoic acid (22:6n-3) and ovule weight (P?<?0.05). High unsaturated fatty acid levels indicated a direct relationship with egg and yolk diameters and also an inverse correlation with ovule surface to volume ratio (P?<?0.l05). Direct relationships were found between polyunsaturated fatty acids and the diameter of egg and yolk as well as the ratio of surface to volume (P?<?0.05). There was a direct correlation between saturated fatty acid content and the number of eggs (per gram) (P?<?0.01). Total lipid and weight of newly hatched larvae represented a direct relationship (P?<?0.05). Despite living in brackish water and migrating to fresh water during the reproductive season, kutum exhibited greater similarity in ovule fatty acid composition to saltwater fish than species in fresh water. Moreover, with respect to biological characteristics, this species shows more significant relationships with n-3 fatty acids than with n-6 fatty acids.     

Fetal cerebral hemodynamic in gestational diabetic versus normal pregnancies: a Doppler velocimetry of middle cerebral and umbilical arteries

Gestational diabetes mellitus (GDM) is one of the most common complications in pregnancies. Evaluating other conditions, including intra uterine growth restriction and pre-eclampsia, some studies have shown significant changes in blood flow velocity of fetal middle cerebral artery (MCA). Our study is one of the few that has aimed to assess the effects of GDM on Doppler parameters of the fetal MCA and umbilical artery (UA) and to compare with normal pregnancies. This cross-sectional study was performed on 66 pregnant women, including 33 women with GDM and the others without it, in Akbar-Abadi University Hospital in Tehran, Iran during 2010–2011. Peak systolic and diastolic velocities, pulsatility index (PI), resistance index (RI) and systolic diastolic ratio (SD) were recorded in UA as well as both right and left fetal MCAs for every recruited pregnant women by means of Doppler ultrasonography. The mean gestational age at the time of examination was 34.45 (SD = 2.62) weeks in GDM group. Although all of the measured Doppler parameters had higher values in GDM pregnancies, the differences were not significant between two groups of study; except for the left fetal MCA-PI, which was significantly higher in GDM group [2.07 (SD = 0.07) vs. 1.85 (SD = 0.74), P = 0.03]. Our results show that gestational diabetes may contribute to an elevated PI in the fetal MCA. Although there is not yet strong proof for the effect of GDM on the fetal brain hemodynamics, the significant higher MCA-PI warrants more attention towards better controlling of the hyperglycemia during pregnancy.     

CD44‐Targeted Docetaxel Conjugate for Cancer Cells and Cancer Stem‐Like Cells: A Novel Hyaluronic Acid‐Based Drug Delivery System

A CD44‐targeted macromolecular conjugate of docetaxel was prepared via a pH‐sensitive linkage to hyaluronic acid and was characterized using NMR, gel permeation chromatography, and differential scanning calorimetry. The conjugated species were further evaluated in terms of drug release, cytotoxicity, cellular uptake, cell cycle inhibition, and subacute toxicity in mice. Cellular microscopic studies revealed that CD44‐expressing cells including MCF‐7 cancer stem cells and MDA‐MB‐231 metastatic breast cancer cells had internalized the conjugates via a selective receptor‐mediated mechanism, leading to cell cycle arrest in the G2/M phase. Hyaluronic acid–docetaxel conjugates showed specific toxicity only in CD44‐expressing cells in vitro, along with a decreased risk of neutropenia and dose‐dependent mortality in vivo. Hyaluronic acid–drug conjugates represent a promising and efficient platform for solubilization of sparingly soluble molecules as well as active and selective targeted delivery to cancer cells and cancer stem cells.     

Lead nitrate induced apoptosis in alveolar macrophages from rat lung

In this work we have attempted to characterize the programmed cell death (apoptosis) in alveolar macrophages exposed to various concentrations of lead nitrate. It was found that after 3 h of exposure a significant increase in superoxide anion production was observed, i.e. the number of trypan blue - exculding cells, was unchanged (< or = 95%) with any dose of lead employed. Agarose gel electrophoresis and diphenylamin reaction analysis revealed the occurrence of internucleosomal DNA fragmentation evaluated using cytological analysis by fluorescence dyes, suggesting that lead nitrate at low concentrations and short periods of exposure leads macrophages into apoptosis. However, time course studies showed that beyond 3 h, toxicity occurs, which could be attenuated by phosphodiesterase inhibitors, such as caffeine, suggesting a possible mechanism involving cAMP.     

Expression of glycodelin protein and mRNA in human ductal breast cancer carcinoma in situ, invasive ductal carcinomas, their lymph node and distant metastases, and ductal carcinomas with recurrence

Glycodelin, previously known as PP14, has been localized in endometrial, ovarian and cervical carcinoma cells. Recently, glycodelin was demonstrated to be expressed in cancerous human breast tissue. In this study, paraffin-embedded slides of carcinoma in situ, invasive carcinomas without metastases, invasive carcinomas with corresponding lymph node metastases, invasive carcinomas with corresponding recurrence and invasive carcinomas with corresponding distant metastases were investigated for glycodelin protein and mRNA expression. Protein expression was found in all cases of carcinoma in situ, in invasive carcinoma without lymph node metastases in 90% of cases, in breast cancer with lymph node metastases in 50% of cases, in breast cancer with recurrence in 38% of cases and in breast cancer with distant metastases in 40% of cases. Results were confirmed by in situ hybridization showing reduced glycodelin expression as lymph node metastasis progressed, compared to carcinoma in situ. Glycodelin mRNA expression is not further reduced in carcinomas with distant metastasis and recurrence compared to carcinoma in situ. Results demonstrate that invasive breast carcinomas without metastases are more likely to express glycodelin. In contrast, cases of breast cancer with metastatic infiltration and recurrence show weak expression of glycodelin. On the basis of these results, we speculate that glycodelin could be used as a prognostic marker for breast cancer.